Those against the building of the UK's second, much longer bit of high speed rail line would like to see its top speeds capped, as a way of making it quieter and more environmentally sound.
According to numbers crunched and published by people working on behalf of the HS2 Action Alliance, limiting the speed of the trains from their proposed maximum of 360km/h to the lesser 3o0km/h would lead to substantial noise and carbon savings, with a possible 6 decibel reduction in noise level when running through fields at full pelt.
The full report [PDF] says reducing speeds would only have a small impact on journey times, with a 4.25 to 5.5 minute increase along the entire current route. It also lowers the technical challenge of building and operating the line, plus the world's current fast train leaders -- France, Japan and Germany -- only have trains that go at 300km/h, so we wouldn't lose international face were target speeds to be quietly lowered.
They would also like HS2 Ltd to be legally required to plant two million trees somewhere, to help mitigate carbon production -- before HS2 even begins construction -- via the HS2 Hybrid Bill. [Guardian]